1 files changed, 13 insertions, 4 deletions

diff --git a/host.c b/host.c
index 2087761..89a8524 100644
--- a/host.c
+++ b/host.c
@@ -10,8 +10,7 @@ struct in_net {
 	struct in_addr addr;
 	struct in_addr mask;
 };
-/* not needed begin */
-#define POPCNT(y) int popcnt##x (uint##y##_t x) { \
+#define POPCNT(y) int popcnt##y (uint##y##_t x) { \
 	int c = 0; \
 	for (int i = 0; i < y; i++) \
 		if (1 << i & x) \
@@ -19,8 +18,6 @@ struct in_net {
 	return c; \
 }
 POPCNT(32)
-unsigned int power2[] = { 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536, 131072, 262144, 524288, 1048576, 2097152, 4194304, 8388608, 16777216, 33554432, 67108864, 134217728, 268435456, 536870912, 1073741824, 2147483648 }; /* ah yes, libmath */
-/* not needed end */
 struct in_net host (struct in_net n, unsigned long long int h /* number of host in the network */) {
 	n.addr.s_addr = ntohl(n.addr.s_addr & n.mask.s_addr);
 	n.mask.s_addr = ntohl(n.mask.s_addr);
@@ -94,3 +91,15 @@ r:
 		*--m = o;
 	return r;
 }
+unsigned long long int ri (unsigned long long int v, int s) { /* 000 100 010 110 001 101 011 111 */
+	int i = s-1;
+	if (!(v & 1 << (s-1)))
+		return v | 1 << (s-1);
+	while (1) {
+		if (!(v & 1 << i))
+			return v | 1 << i;
+		if (!i) /* rollover */
+			return 0;
+		v &= ~(1 << i--);
+	}
+}